This proposal is to request support for a Keystone Symposia meeting entitled "New Insights into Healthspan and Diseases of Aging: From Molecular to Functional Senescence", organized by Sean M. Oldham, David A. Sinclair, Jan Vijg and Heidi Scrable, which will be held in Tahoe City, California from January 31 - February 5, 2010. Aging can be defined as the gradual loss of the ability of the organism to maintain homeostasis. Our aim will be to focus on the molecular and cellular mechanisms by which tissue and organ function deteriorate and homeostasis fails rather than on longevity itself, which has been the theme of previous Keystone Symposia meetings on aging. Work from a variety of models is recognizing that organisms, especially humans, are complicated systems in which interventions that extend lifespan might not necessarily block the aging and loss of function in specific organs or tissues and vice versa. Continuing this approach will help us gain an understanding and appreciation of the complexity that underlies aging in humans. The aim of this meeting is to reveal the integration and communication between pathways and systems during functional aging and their relationship with longevity. This meeting will highlight important questions to address in future research. Most importantly, what are the common and disparate causes underlying the cellular and physiological mechanisms responsible for human senescent phenotypes? PUBLIC HEALTH RELEVANCE: The Keystone Symposia meeting on New Insights into Healthspan and Diseases of Aging: From Molecular to Functional Senescence will bring together researchers who study aging using experimental systems that range from the test tube to the animal. Our aim will be to focus on the molecular and cellular mechanisms by which tissue and organ function deteriorate and homeostasis fails rather than on longevity itself. Aging research needs to move beyond the simple systems that have been useful in the past to an appreciation of the complexity that underlies aging in humans.